ANL, Argonne
Funding: Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
A superconducting planar undulator is under development at the Advanced Photon Source (APS). The initial R&D phase of the project includes intensive magnetic modeling performed with the Opera 2d and 3d software packages. This simulation addresses questions of magnetic design of the undulator including calculation of peak field on the undulator axis and maximum field in the conductor, superconductor load line optimization, and design of the undulator ends and correction coils. Results of the magnetic simulation are presented in the paper.
ANL, Argonne
Fermilab, Batavia
Funding: Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
An extensive R&D program is underway at the Advanced Photon Source (APS) with the aim of developing a technology capable of building a 2.4-m-long superconducting planar undulator for APS users. The initial phase of the project concentrates on using a NbTi superconductor and includes magnetic modeling, development of manufacturing techniques for the undulator magnet, and design and test of short prototypes. The current status of the R&D phase of the project is described in this paper.
CIAE, Beijing
TRIUMF, Vancouver
The design and cryo-test system of a plug-in cryopump used in CYCIAE-100 is introduced. The plug-in cryopump consists of two cryopanels, a baffle, a half-opened shield, and two GM refrigerators (CGR411, CVI) which power is 83W/80K at the first stage and 7.5W/20K at the second stage, its designed pumping speed is 15000L/s. Cryo-test system of plug-in cryopump employs the flux method to test pumping speed, cool-down time, ultimate pressure, temperature distribution on cryopanel and capacity at the pressure of 10-6Pa to 1Pa. The heat load calculation of cryopanel and shield including baffle is conducted in succession. In the end a comparison between design parameters and test results is drawn.
LBNL, Berkeley, California
Funding: Supported by the U.S.Department of Energy under Contract No. DE-AC02-05CH11231.
Insertion quadrupoles with large aperture and high gradient are required to achieve the luminosity upgrade goal of 1035 cm-2 s-1 at the Large Hadron Collider (LHC). In 2004, the US Department of Energy established the LHC Accelerator Research Program (LARP) to develop a technology base for the upgrade. The focus of the magnet program, which is a collaboration of three US laboratories, BNL, FNAL and LBNL, is on development of high gradient quadrupoles using Nb3Sn in order to operate at high field and with sufficient temperature margin. Program components address technology issues regarding coil and structure fabrication, quench performance, field quality and alignment, length scale-up, quench protection, radiation hardness, conductor and cable. This paper reports the current status of model quadrupole development and outlines the long-term goals of the program.
Far-Tech, Inc., San Diego, California
We describe the design and construction status of a compact, 830 kW multi-beam klystron (MBK) for driving 1300 MHz cryomodules. The applications for this tube range from ILC and ILC test facilites to Project X. The use of low gun voltage (36 kV) simplifies the modulator and gun socket requirements. A high efficiency, predicted to be > 65%, will allow the klystron to be used in applications requiring low overall site power and high wallplug efficiency.
KEK, Ibaraki
High-gradient RF breakdown studies have been in progress at Nextef (New X-band Test Facility at KEK) since 2006. To study the characteristics of different materials on high-field RF breakdown, we have performed high-gradient experiments by using narrow waveguides that has a field of around 140 MV/m at 50 MW power. Breakdown rates of stainless-steel and copper cases were measured and the results are described in this paper.
CLASSE, Ithaca, New York
Fermilab, Batavia
Funding: Work Supported by the U.S. Department of Energy
To build the ~14,000 cavities required for the ILC each of the three world regions must have a sizable industrial base of qualified companies to draw cavities from. One of these companies, Niowave Inc., recently manufactured six 1.3 GHz single-cell cavities for qualification purposes. All six cavities achieved gradients above 25 MV/m before they were limited by the available RF power (Q-slope) or quenched. This paper will report the results of cold tests for all six cavities and on the causes of quench determined by 2nd sound detection and optical inspection.
CLASSE, Ithaca, New York
Funding: Work Supported by the NSF and the DOE
An innovative reentrant cavity design instigated the initial, highly successful, superconducting niobium reentrant-single-cell cavity tests at Cornell and KEK. Prompted by the success of the single cell program a joint effort of Cornell University and Advanced Energy Systems (AES) fabricated two multiple-cell reentrant cavities: a three-cell and a nine-cell cavity. This paper reports the development status of these two cavities. First, the results of cold tests, superfluid helium defect location and repair work on the reentrant nine-cell cavity will be presented. Second, the results of cold tests, including defect location and repair efforts of the reentrant three-cell cavity will be presented.
PAL, Pohang, Kyungbuk
Funding: Supported by the Korea Ministry of Science and Technology mhchun@postech.ac.kr
The RF system for the Pohang Light Source (PLS) storage ring is operating at total maximum RF power of 300kW with four 75kW klystron amplifiers and four PF-type normal conductivity(NC) RF cavities for 190mA at 2.5GeV. The PLS will be upgraded from 2.5GeV/200mA to 3.0GeV/400mA in the near future. Therefore the RF system should be greatly upgraded to supply total 627kW beam power. We are investigated the some upgrade ways with adding NC cavities or new super conductivity(SC) RF cavities. According to the cavity type, the high power RF system will be adjusted the total RF power, and source type and quantity such as klystron or IOT. This paper describes the present operation status and several optional ways of high power RF system for the upgrade project of PLS storage ring
RadiaBeam, Marina del Rey
UCLA, Los Angeles, California
The fixed-field alternating-gradient (FFAG) betatron has emerged as a viable alternative to RF linacs as a source of high-energy radiation for industrial and security applications. RadiaBeam Technologies is currently developing an FFAG betatron with a novel induction core made with modern low-loss magnetic materials. The principle challenge in the project has been the design of the magnets. In this paper, we present the current status of the project, including results of the magnet design and testing.
LBNL, Berkeley, California
Funding: This work was supported by the Director, Office of Science, U. S. Department of Energy under Contract No. DE-AC02-05CH11231.
The Advanced Light Source (ALS) is a third generation synchrotron light source that has been operating since 1993 at Berkeley Lab. Recently, the ALS was upgraded to achieve Top-Off Mode, which allows injection of 1.9GeV electron beam into the Storage Ring approximately every 30 seconds. Modifications required for Top-Off operation included replacing the booster dipole and quadrupole magnet power supplies to increase the peak booster beam energy from 1.5GeV to 1.9GeV. Each new power supply was originally controlled by an analog controller that performs the current feedback loop and, in concert with other modules in the control chassis, determines the output of the ramped power supply. The new digital power supply controller performs the current feedback loop digitally to provide greater output stability and resolution. In addition, it provides remote monitoring of feedback loop signals, interlocks, and status signals, as well as remote control of the power supply operation via Ethernet. This paper will present the ALS Digital Power Supply Controller module requirements and design.
SLAC, Menlo Park, California
Funding: Work supported by the U.S. Department of Energy under contract number DE-AC02-76SF00515
This paper will report on the test results of a prototype 1320 watt power module for a high availability power supply. The module will allow parallel operation for N+1 redundancy with hot swap capability. The two quadrant output of each module allows pairs of modules to provide a 4 quadrant (bipolar) operation. Each module employs a novel 4 FET buck regulator arranged in a bridge configuration. Each side of the bridge alternately conducts through a small saturable ferrite that limits the reverse current in the FET body diode during turn off. This allows hard switching of the FETs with low switching losses. The module is designed with over-rated components to provide high reliability and better then 97% efficiency at full load. The modules use a Microchip DSP for control, monitoring, and fault detection. The switching FETS are driven by PWM modules in the DSP at 60 Khz. A Dual CAN bus interface provides for low cost redundant control paths. The DSP will also provide current sharing between modules, synchronized switching, and soft start up for hot swapping. The input and output of each module have low resistance FETs to allow hot swapping and isolation of faulted units.
SLAC, Menlo Park, California
Funding: Work supported by the U.S. Department of Energy under contract DE-AC02-76SF00515
A program is underway at SLAC to develop a Marx-topology klystron modulator for the International Linear Collider* project. It is envisioned as a smaller, lower cost, and higher reliability alternative to the bouncer-topology baseline design. The application requires 120 kV (±0.5%), 140 A, 1.6 ms pulses at a rate of 5 Hz. The Marx constructs the high voltage pulse without an output transformer, large at these parameters, by instead combining a number of lower voltage cells in series. The modularity of the Marx topology is further exploited to achieve a redundant, high-availability design. The ILC Marx employs solid state elements; IGBTs and diodes, to control the charge, discharge and isolation of the cells. The SLAC designs are oil-free; air is used for high voltage insulation and cooling. The first generation prototype, P1, is undergoing life testing. Development of a second generation prototype, P2, is underway. Status updates for both prototypes will be presented.
*ILC Reference Design Report, http://www.linearcollider.org/cms/?pid=1000437
SLAC, Menlo Park, California
ORNL, Oak Ridge, Tennessee
Funding: Work supported by the Department of Energy under contract No. DE-AC02-76SF00515.
SLAC National Accelerator Laboratory is developing a next generation H-bridge switch plate*, a critical component of the SNS High Voltage Converter Modulators**. As part of that effort, a new IGBT gate driver has been developed. The drivers are an integral part of the switch plate, which are essential to ensuring fault-tolerant, high-performance operation of the modulator. The redesigned drivers improve upon the existing gate drives in several ways. The new gate driver has improved fault detection and suppression capabilities; suppression of shoot-through and over-voltage conditions, monitoring of excess di/dt and Vce,sat, and redundant power isolation are some of the added features. Also, triggering insertion delay is reduced by a factor of four compared to the existing driver. This presentation details the design and performance of the new IGBT gate driver. A detailed schematic and description of the construction are included. Operation of the fast over-current detection circuits, active IGBT over-voltage protection circuit, shoot-through prevention and control power isolation breakdown detection circuit are discussed.
*W. A. Reass, et al., “Design, Status, and First Operations of the Spallation Neutron Source Polyphase
”, PAC, 2003
**M.A. Kemp, et al., “Next Generation IGBT Switch Plate
,” LINAC, 2008.
SLAC, Menlo Park, California
Funding: Work supported by the Director, Office of Science, High Energy Physics, U.S. DOE under Contract No. DE-AC02-76SF00515.
CMAD is a new code modeling the electron cloud effect driven instability by applying an electron-beam interaction at every element of a beam line, reading a MAD description of the accelerator optics as input. CMAD is parallelized and optimized for speed. It is especially suited for the modeling of incoherent electron-cloud effects for which the spatial distribution of electrons is particularly important. This talk will review the physics, describe the design concept, the present status, benchmarking exercises, and example applications.
PKU/IHIP, Beijing
Funding: Supported by National Basic Research Program(No. 2002CB713600) and NSFC(No. 10775010).
The 3.5-cell cavity for the PKU DCSC photoinjector requires the main coupler and the pickup be on the same side of the cavity, which will cause crosstalk between them. At room temperature, serious distortion of the RF response is caused. This paper applies a clear understanding of the RF signal; numerical and experimental study shows that the crosstalk will be negligible in superconducting (SC) status. Furthermore, a method to calculater resonant frequency and loaded quality factor from the crosstalk signal is provided
UCLA, Los Angeles, California
BNL, Upton, Long Island, New York
Funding: DOE
A study of target parameters for a high-intensity, liquid mercury jet target system for a neutrino factory or muon collider is presented. Using the MARS code, we simulate particle production initiated by incoming protons with kinetic energies between 2 and 100 GeV. For each proton beam energy, we optimize the geometric parameters of the target: the mercury jet radius, the incoming proton beam angle, and the crossing angle between the mercury jet and the proton beam. The number of muons surviving through an ionization cooling channel is determined as a function of the proton beam energy
DESY, Hamburg
The DESY Engineering Data Management System, DESY EDMS, is a fully Web-based central information management platform at the European XFEL and the Global Design Effort for the International Linear Collider (ILC GDE). It provides functionality for managing documents and 3D CAD data and for performing configuration and change management. It can control complex information structures and keep track of their dependencies and history, i.e. their evolution over time. Due to its powerful capabilities for automating workflows and controlling information access, the DESY EDMS can coordinate processes and manage authorizations and responsibilities in large and complex organizations, which may include several institutes and industrial partners. Applications of the DESY EDMS range from small-scale document management for work groups, up to managing the complexity of world-wide collaborations during design and construction activities. The poster describes the architecture of the DESY EDMS, introduces some of its use cases and reports lessons learned in developing and operating the system.
DESY, Hamburg
The European XFEL has started the construction of the underground buildings. Now, the detailed design of the technical infrastructure has to be completed, covering HVAC (heating, ventilation, air conditioning), MEP (mechanical, electrical and plumbing), communication, transportation and safety. The design process is centered around the XFEL Roombook: The XFEL Roombook contains a complete catalog of XFEL buildings, floors and rooms. Future user groups specify requirements on their rooms, which are collected in a central database (Requirements Management System, RMS). Engineers create floor plans and design drawings based on the requirements. Project members can access room information, requirements and floor plans through the Web interface of the XFEL Roombook. The XFEL Roombook is in production since summer 2009 and has become a well accepted information platform for infrastructure design. The paper describes the planning process, the supporting tools and lessons learned.
POSTECH, Pohang, Kyungbuk
Funding: Work supported by MEST and PAL.
Recently the Korean government successfully completed a large-scale facility, called the KSTAR, a fully superconducting tokamak after joining in the ITER project. It made renewed interests in large-scale scientific facilities to promote basic and applied research capabilities. The next projects include a space project and particle accelerators. The immediate one in accelerator program is the PLS-upgrade, and its budget is now in the congress for FY2009. The others are in the middle of consensus making process: a heavy ion accelerator for rare isotopes and a new synchrotron light source other than the PLS-upgrade and the ongoing proton linac program. This paper will give an overview of the status and prospects of major particle accelerator initiatives in Korea. The paper will also include descriptions of the significant contributions undertaken by Korea through collaborations with major international facilities using particle accelerators. Finally, the paper will outline how industry, government and universities in Korea are collaborating on particle accelerator R&D.
LANL, Los Alamos, New Mexico
Funding: US Department of Energy
Future improvements to the Los Alamos Neutron Scattering Center (LANSCE) include new Beam position and phase measuring systems that operate at 201.25 to 805 MHz. An effort is underway to build and test prototype electronics for these applications. We plan to use direct down conversion to 35 to 115 MHz followed by COTS FPGA hardware for in-phase and quadrature-phase (I/Q) signal processing. Self- calibration and system diagnostics circuits will be included. We are reporting on the status of these efforts.
NSRRC, Hsinchu
The vibration issue is significant issue about the accelerator commission. The utility system has many mechanical parts and induces severe vibrations. For the purpose of tracing vibration source and preventing facility failure, the on-line vibration measurement and trace system has been developed. The system adopt programmable automation controller with FPGA function to conduct a series of data acquisition and algorithm. The system including specific analysis of time and frequency domain has also been integrated into the previous monitor and archive system. The user friendly interface may provide on-line analysis and trace vibration source via network anywhere and anytime.
CAEP/IFP, Mainyang, Sichuan
The capability of the chromatic correction of Zumbro Lens lies on the angle-position correlation, which is obtained by passing the beam through an expander or quadruples. However even after a long distance drift downstream the expander, the angle-position correlation can not be perfect because of the existence of finite emittance. This paper discusses the influence of the emittance to the chromatic correction and the optimization of beam status in phase space at the entrance of the expander.
The University of Tokyo, Nuclear Professional School, Ibaraki-ken
JASRI/SPring-8, Hyogo-ken
In XFEL/SPring-8, it requires ultra high-brightness electron bunches with ultralow slice emittance and bunch duration of 30 fs (FWHM) in a lasing part. In order to measure such bunches, we are developing a single-shot, non-destructive, real-time 3-D bunch shape monitor based on EO sampling with a manner of spectral decoding. It consists of a radially polarized probe laser and 8 EO-crystals, which surround a beam axis azimuthally and their crystal-axes are radially distributed as well as Coulomb fields of electron bunches. The probe laser has a linear-chirped broad bandwidth (> 400 nm at 800 nm of a central wavelength) for higher temporal resolution, and a hollow shape to avoid interacting with electron bunches. As an EO crystal, we investigate the feasibility of an organic crystal such as a DAST for 20-fs temporal response. This monitor can measure not only longitudinal but also transverse charge distribution at the same time. These real-time 3-D bunch shape measurements are very important to optimize electron bunches for XFEL operation. We present the scheme of this monitor with its estimation in detail and report the developing status for probe laser and organic-EO-crystals.
UCR, Riverside, California
The Muon Ionization Cooling Experiment (MICE) is being built at the Rutherford Appleton Laboratory (RAL) to test ionization cooling of a muon beam. Successful demonstration of cooling is a necessary step along the path toward creating future high intensity muon beams in either a neutrino factory or muon collider. MICE will reduce the transverse emittance of the beam by 10%, and spectrometers using particle physics techniques will measure the emittance reduction with an absolute precision of 0.1%. This measurement will be done with scintillating fiber tracking detectors nested inside solenoid magnets on either side of the cooling channel. Each fiber tracker contains five stations with 3 layers of fibers rotated 120 degrees with respect to each other, thereby allowing reconstruction of hit points along the path of the muons. Light is carried from the active fiber volume by clear waveguide fibers where it is detected using VLPCs (Visible Light Photon Counters). The details of the tracker commissioning using cosmic rays will be discussed in addition to the status and performance of the readout electronics*.
*Submitted on behalf of the MICE collaboration.
USTC/NSRL, Hefei, Anhui
As low injection energy and multi-turn injection at HLS, the task of diagnosing and curing coupled-bunch instabilities becomes ever harder. The transverse analog feedback system has been redeveloped to improve effect, recently. In this paper, the new improved designs are described and new system's commissioning results are discussed. The transverse coupled bunch instability at 200MeV injection status is also experimentally studied.
BNL, Upton, Long Island, New York
Stony Brook University, Stony Brook
Funding: Work performed under auspices of the U.S. Department of Energy under Contract No. DE-AC02-98CH10886 with Brookhaven Science Associates, LLC
This paper presents a new extension to EPICS, approaching the Data Distributed Service (DDS) interface based on the Channel Access protocol. DDS is the next generation of the middleware industrial standards, bringing a data-centric publish-subscribe paradigm to distributed control systems. In comparison with existing middleware technologies, the data-centric approach is able to provide a consistent consolidated model supporting different data dissemination scenarios and integrating many important issues, such as quality of service, user-specific data structures, and others. The paper considers different features of the EPICS-DDS layer in the context of the accelerator high-level environment and introduces a generic interface addressing various types of accelerator toolkits and use cases.
BNL, Upton, Long Island, New York
Funding: Work performed under auspices of the U.S. Department of Energy under Contract No. DE-AC02-98CH10886 with Brookhaven Science Associates, LLC.
A distributed software architecture for high level applications is under development at the NSLS-II (National Synchrotron Light Source II) project. One of the important issues is to make accelerator simulation model run on a standalone model server. To enhance the capacity of the model server, it is required to have a set of narrow and general API to accommodate various existing tracking codes. A preliminary study for the API development has been started at NSLS-II based on The MMLT (Matlab Middle Layer Toolkit).A new interface is developed for the MMLT to support another simulation engine known as Tracy. A virtual accelerator is also built for the NSLS-II storage ring based on the Tracy code and the EPICS framework. Although we don't have a real machine, we can evaluate and develop our high leval application with the support of virtual accelerator. This paper describes the current status of the software architecture for high level applications.
CERN, Geneva
The core task of the commissioning of the LHC technical systems was the individual test of the 1572 superconducting circuits of the collider, the powering tests. The two objectives of these tests were the validation of the different sub-systems making each superconducting circuit as well as the validation of the superconducting elements of the circuits in their final configuration in the tunnel. A wide set of software applications were developed by the team in charge of coordinating the powering activities (Hardware Commissioning Coordination) in order to manage the amount of information required for the preparation, execution and traceability of the tests. In all the cases special care was taken in order to keep the tools consistent with the LHC quality assurance policy, avoid redundancies between applications, ensure integrity and coherence of the test results and optimise their usability within an accelerator operation environment. This paper describes the main characteristics of these tools; it details their positive impact on the completion on time of the LHC Hardware Commissioning Project and presents usage being envisaged during the coming years of operation of the LHC.
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
The ALICE accelerator is a 35MeV energy recovery linac prototype at Daresbury in the U.K. Due to the highly experimental nature of the accelerator, there has been a strong influence of accelerator physicists in the high-level control software for the machine. Starting from the underlying EPICS-based control system, a suite of interactive commissioning software has been built using traditional software approaches, such as LabVIEW, as well as experimenting with interactive, rapid prototyping programming languages, such as Mathematica. Using the EPICS Channel Access protocols, the control system is flexible and extensible. A wide range of tools can be used to develop and debug high-level software, allowing machine physicists to use the most appropriate and familiar tools for software development.
LBNL, Berkeley, California
Funding: Supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
The Advanced Light Source (ALS) is a third generation synchrotron light source that has been operating since 1993 at Berkeley Lab. Recently, the ALS was upgraded to achieve Top-Off Mode, which allows injection of 1.9GeV electron beam into the Storage Ring approximately every 30 seconds. The ALS Top-Off Mode Beam Current Interlock System was installed to prevent the potential hazard of injected electrons propagating down user beam lines. One of the requirements of this interlock system is a fast response time from detected event to injection trigger inhibit. Therefore, solid state devices, not electro-mechanical relays typically used in accelerator safety systems, must be used to implement the trigger inhibit logic. An FPGA-based solution was selected for this function. Since commercial FPGAs are not rated for high reliability or fail-safe operation, some of the logic resources were used to perform system self-checking to reduce the time to detect system failures and increase reliability. The implementation and self-checking functions of the Extraction Trigger Inhibit Interlock System will be discussed.
SLAC, Menlo Park, California
Funding: SLAC/DOE Contract DE-AC02-76-SF00515
A state-of-the-art Machine Protection System for the SLAC Linac Coherent Light Source has been designed and built to shut off the beam within one pulse during 120 Hz operation to protect the facility from damage due to beam losses. Inputs from beam loss monitors, BPMs, toroids and position switches of insertable beam line devices are connected to a number of Link Node chassis placed along the beam line. Link Nodes are connected with a central Link Processor in a star topology on a dedicated gigabit Ethernet fiber network. The Link Processor, a Motorola MVME 6100, processes fault data at 360 Hz. After processing, rate limit commands are sent to mitigation devices at the injector and just upstream of the entrance of the sensitive undulator beam line. The beam's repetition rate is lowered according to the fault severity. The SLAC designed Link Nodes support up to 96 digital inputs and 8 digital outputs each. Analog signals are handled via standard IndustryPack (IP) cards placed on the Link Node motherboards with optional transition boards for signal conditioning. A database driven algorithm running on the Link Processor provides runtime loadable and swappable machine protection logic.